As one means for administering a drug via the skin, a microneedle is known. For example, Patent Literature 1 discloses a microneedle sheet that includes a plurality of microneedles formed in a sheet substantially along a principal surface of the sheet. In the microneedle sheet, the sheet is bent so as to raise the microneedles from the principal surface, and the raised microneedles pierce the skin.
A microneedle device including this sheet-like microneedle is also known. For example, Patent Literature 1 discloses a microneedle device in which the above-described sheet-like microneedle is fixed to an affixing surface of a base material which comes into contact with the skin when the microneedle device is applied to the skin so that the sheet-like microneedle is protected by a release film.